I'm looking for airbags for a JD planter with Precision Planting Airforce up/down brackets.  I've got the up bags and looking for the down bags.  Does anyone have a part number for an aftermarket source for these?  Deere and precision are spendy for these air bags and I know there are numerous other applications that use these so there has to be some kind of cross over part number.  I got a sample one from Deere hoping I could get a part number off of it that I could use to cross reference...but no luck.

Thanks