Depending on location, region, and/or country, your options may vary.
•Apple - Find Locations - country selector: Sales, service, training,
certification, & consulting. + Note service provider locator link below.
https://locate.apple.com/country
There are authorized Apple service providers who are independent
shops that could repair older models and look around for parts if the
computer is not a current model series. Happens a lot, since the new
ones have recent inventory; and older ones need repairs & parts.
You could look up your model identifier series portable computer in
a database such as Apple Support to be sure the exact build, then
use that info to look into repair guides and replacement part specs.
{If the model is the Aluminum 13-inch MacBook, Late 2008, that has
different parts and procedures to repair & replace them, than the
Late 2008 White polycarbonate 13-inch MacBook. There was only
one aluminum MacBook in the series, between 2006 & 2010.}
•How to identify MacBook models
•How to identify MacBook Pro models
See iFixit.com Apple portable guides for repair info & any reference
number for keyboard. Some of these require extensive take-apart
and perhaps the part can be costly if it is a unibody model with the
keyboard or touchpad fixed to the computer's body.
https://www.ifixit.com/Device/Mac_Laptop
Everymac.com has details about build models across the brand.
http://www.everymac.com/
You may be able to decide if your DIY skills, and researched part
availability, could be suited to a self-repair attempt; however as
difficult as these can be, an authorized Apple trained technician
or an Apple Specialist, who has experience in these models, is a
better match to see about the repair task.
So depending on where you are located, the options vary. In some
places, there aren't many. Where are you?
In any event... hopefully you can get the correct service + parts.
Good luck & happy computing! 🙂