Is it possible for the display module to be replaced in an iPhone 5/5s? Thanks in advance :)

After getting wet, the iPhone will corrode and cause all kinds of future problems. Also in order for rice to remove the moisture it normally takes a wake and not a day. Have powered it on while it still contained moisture there is not tell what you burned out in by doing that.

Since the iPhone is considered not user repairable, opening it to do any repair work on it will cause Apple to refuse to have anything to do with it all afterwards.

Instead I recommend you take it Apple and purchase an out of warranty replacement for it.

The screen has probably failed because the water has fried the circuits

You should be eligible for an Out of Warranty exchange at an Apple Genius bar

if in the US it is $269 + tax similar in other major Currencies

This is the offering

Apple’s One Year Limited Warranty
Apple’s One Year Limited Warranty for iPhone covers your iPhone and Apple accessories against defects in materials and workmanship for one year from the original date of purchase. It doesn’t cover accidental, cosmetic, or liquid damage or damage due to unauthorized modifications. See the warranty for complete details.
Read Apple’s One Year Limited Warranty for iPhone

AppleCare+ for iPhone
Purchasing AppleCare+ extends the hardware coverage to two years from the original purchase date of your iPhone and covers two incidents of accidental damage, each with a $79 service fee plus applicable tax. AppleCare+ also includes Express Replacement Service so you can get a replacement before sending in your iPhone.

If you didn’t buy AppleCare+ with your iPhone, you can buy it within 60 days of purchase. Take your iPhone to an Apple Retail Store or call Apple. We’ll verify the purchase date and confirm that your iPhone has no existing damage.
Learn more about AppleCare+
Read the AppleCare+ Terms and Conditions

Screen repair service pricing
Repair and replacement costs depend on your iPhone model and your AppleCare product coverage. Apple will run a diagnostic test to determine whether your iPhone has experienced additional damage. If it has, or if it needs other repairs, you may need to pay an out-of-warranty service fee. Accidental damage isn't covered under the Apple One Year Limited Warranty.

Model	Screen repair cost
iPhone 6	$109
iPhone 6 Plus, iPhone 5s, iPhone 5c, iPhone 5	$129

Plus a $6.95 shipping fee, if required. Fees are in USD and exclude local tax. Pricing is for service through Apple. The final service fee we charge will be determined during testing. Pricing and terms vary for service through an Apple Authorized Service Provider.

Out-of-warranty repair service
If your repair isn’t covered by Apple’s One Year Limited Warranty, AppleCare+, or AppleCare Protection Plan, your iPhone might be eligible for out-of-warranty service. For example, liquid damage isn’t covered by warranty but might be eligible for out-of-warranty service. Some damage isn’t eligible at all, for example if your device has been broken into multiple pieces. See Apple’s Repair Terms and Conditions for complete details.
Read Apple’s Repair Terms and Conditions

Model	Out-of-warranty service fee	Battery service*
iPhone 6 Plus	$329	$79 *available only if battery fails Apple’s diagnostic test
iPhone 6	$299
iPhone 5s, iPhone 5c, iPhone 5	$269
iPhone 4s	$199
iPhone 4, iPhone 3GS, iPhone 3G, Original iPhone	$149

Plus a $6.95 shipping fee, if required. Fees are in USD and exclude local tax. Pricing is for service through Apple. The final

Always best to say where if not US ,this world wide Community is none the less very US centric

Out-of-Warranty Service

If you own an iPhone that is ineligible for warranty service but is eligible for out-of-warranty (OOW) service, Apple will service your iPhone for the out-of-warranty service fee listed below.

Please note out-of-warranty repair service fees from your carrier may be different than those listed below.

Model	Out-of-warranty service fee
iPhone 6 Plus	£ 266.44
iPhone 6	£ 236.44
iPhone 5s, iPhone 5c, iPhone 5	£ 206.44
iPhone 4s	£ 166.44
iPhone 4	£ 126.44

The out-of-warranty service fee includes a £ 7.44 shipping fee, which applies only if service is arranged through Apple and requires shipping. All fees are in British pound sterling and include VAT. iPhone out-of-warranty service may also be available from your wireless carrier. Pricing may vary.

So UK price for a 5S is £199