What do they have on them? How broken? How close is your BSL to your friend's? Are you going to mount them yourself or have a shop do it?
My first plan would be to get something with the same hole pattern if my BSL would fit. If not then I'd troll thrift stores for a pair of skis with usable bindings (all metal if older but not too old regardless) and mount them up.
If you're going to pay a shop to do it (HIGHLY RECOMMENDED), then just bring them there and see what they have on clearance.
I guess one thing to consider with park skis is that you probably want them centered so going +- of the old mount point isn't as much of an option. Whatever difference you have in BSL may come in to play with binding selection. If you are close but not close enough to use the same holes perhaps a different brand/pattern would be better so the new holes aren't too close to the old ones..