I wouldn't discount the epoxy solution so quickly. Many of today's industrial adhesives cure to a hardness rivaling metal. I owned an AA-5 Traveler (four-seat, single-engine piston aircraft) for nearly a decade. The major components of the aircraft were bonded together, a bond which held strong and true for 4000+ flying hours since it was built in 1972.
If you're concerned about subsequent removal, apply a bit of wax on the threads of the bolt before applying the adhesive -- the wax between the the epoxy and the bolt prevents a bond.
I don't know what the kit you were referring to costs, but it shouldn't cost anything more than the epoxy kits at Wally-world. At least if you try the Wally-world product and it doesn't work for you, you're only out a couple of bucks. Just make sure you read the label and ensure the product will adhere to metal.
Adhesives are very process sensitive -- you must follow the directions carefully. If you don't throughly clean contaminants off the intended bonding surface you will severly compromise the bond. Adhesives especially don't like lubricants (especially silicones) and waxes.
Regards,
Mark
BTW,