Yep, only I vote for 518 more than 515 simply because it fixtures (holds your parts together) a bit more quickly than 515.
Instead of an Amazon-type place, I suggest going to one of your local Industrial Distribution/Bearing/Power Train houses like Motion Industries, Applied Industrial Technologies, Grainger, Fastenal. If they don't have the stuff, you'll get it the following day.
Some part numbers:
pn. 51817 Loctite 518 Gasket Eliminator, 6ml "Travel Size"
pn. 51831 Loctite 518 Gasket Eliminator, 50ml
No, really, the mustache means I love you.