It's a stock QB78 stock with a bedliner finish and one of those cheek risers they sell at archer airguns. Can't comment on the buttstock extension, but it also appears to be the archer airguns model. At $20 starting bid and almost $12 shipping, it's not a "bad" deal, but not impressive...I think the normal wooden stock kit is about $25. Who knows, it could be bedlinered because the original owner cracked it and wants to hide flaws, or maybe just because it was a poor stock to begin with. Either way someone pretty much just dolled up a stock piece of equipment, if you own a QB and the original stock, just buy the cheek riser and a can of bedliner...it's cheaper:)
Dan