bobcat sells the kit here, https://shop.bobcat.com/mount-kit-6586933
not cheap. i would stick with the newer 607 over an older model. the balls kinda suck. i'll keep my eyes open for you.
because when you are pulling the trigger it's closing the bucket, and its already close, to operate the bucket you should be using the thumb switch on the top of the right stick
I ordered a set camso sks753s on rims, on ebay for i think $1150 a couple years ago. the traction is outstanding, and the best snow tire for a bobcat i've ever used.