You can't use that phone on your current provider. You're using a
CDMA network, while the phone that you found is used for
GSM.
CDMA &
GSM are both digital technologies, but are not compatible with each other. You can't buy a Verizon
SIM because there is no such thing.
SIM cards are used mainly for
GSM phones only. If you want to make some money off of it, have it unlocked and sell it.