Seems like people like the replacement valves except for the 15 USD cost. I've found them to work well. I'd be skeptical about several glue adhesives -- fine for the first application, but the residue could be a problem with subsequent repairs.
Has anyone tried the same stuff that's on the replacement valves? I'm pretty sure it's the same stuff used in 3M transfer tapes (without backing). Note: this is not the typical double-sided tape -- it's just the goo that's used on tape -- pressure sensitive adhesive (PSA). I'm thinking that you'd clean off the old valve and bladder, apply the transfer tape to the valve, cut out the center, remove the liner, and apply to the bladder just as you would the new valve.
Several flavors can be bought here:
I'm thinking 9482PC would be good, but they don't sell it wide enough (perhaps it can be overlapped ok since the goo is very conformal, or buy custom cut). F9460PC may be another good choice.