Can't say about the Amulet. I'd probably allow it if I were running a published module and it were part of the treasure, but if I were running a homebrew and the PC already had Hands as Weapons, I probably wouldn't include it.
It is not so much out of a concern over its power- I excise precious little from my game- but just because I don't think it would be needed. It would be kind of redundant.
OTOH, it would obviate the player's perception that he needs for the Monk to spend GP getting his hands enchanted with the abilities in the Amulet...
I have a monk as well. Are d20 systems books allowed in your campaign? If so, I know of MANY REALLY GOOD items designed for monks that are from maybe 3,000 to 30,000 gp and then some that go above that. If you are able to use those books I will share them with you. Let me know.
MB
I'd like to note that becoming Large in and of itself will not grant a Strength bonus.Being large moves your unarmed damage to the next category, plus a bonus to strength.
You are not using the most recent version of Kensai as found in the Complete Warrior, where you must make a Concentration check to use Power Surge again.The aforementioned Kensai has another benefit (besides their weapon enhancement power) that makes them great for monks: a +8Str boost that is 1) untyped and 2) usable once per day...unless you make a Wisdom-based DC check (like a Monk can't make a few of those).