If I buy an iPhone 5 without a SIM card can I get the phone prepaid on verizon

The only place you can get an unlcocked phone is in an Apple Store.

Wether or not you can get it on a prepaid plan with Verizon only Verizon can answer. Contact Verizon and ask them.

No. Last I checked, Verizon only supports the 4 and 4S on prepaid. And, in order for a phone to work on Verizon's network, you have to buy the Verizon version of the phone, not the factory unlocked one.