You could probably bolt those bindings and use your current boots on your new board if you're really tight for cash, but I definitely do not recommend you start modifying your gear. Lamar/Liquid are entry level products, so IMO, go and get new boots and bindings for that new board. Flick's setup of Arsenals and Cirro would be a good choice for freeriding and they could be found for a good price online. Just try on the Cirro's first and see if you like them. Like everyone has already mentioned, the boots is one of your most important gear, so don't skimp here.