Chainrings for Shimano FC-M760 crank worn out, need help

It's a very populous crank and generally speaking any aftermarket/replacement type chainrings will go on it. It tends to be true that the designated Shimano chainrings make the best replacements for their cranks in terms of performance, or at least avoid minor weirdness with spacing or spider fit, but it's rare for those issues to be insurmountable when fitting aftermarket replacement rings on to a mainstream crank like this.

There are some 104 rings where the rounded contour of the spider can be a mismatch. If memory serves you get into this from mounting Truvativ/SRAM rings on Shimano cranks, but I may have that in reverse. You knock the ring down slightly with a half round file and it's fine.

Some brands to look out for aftermarket replacements are Origin8, Dimension, Blackspire, Vuelta, and TA. The 2020 parts shortages have not hit generic replacement chainrings that hard and I see some of these are still readily available from distributors.

I have a list of cranks here.

https://docs.google.com/spreadsheets/d/1HdcNgmQKFA-lAqQJ3lXQ8SwA4tblAKiOXe9XYJJHYN8/edit

There are a few alternates of similar quality and vintage, such as Hone, XT, XTR, LX, SLX, and Saint.

Alternatively a cheap modern 9-speed HT2 crankset could be very cheap. E.g, FC-MT300-3.

You could remove the chainrings from that and fit them to your XT chainset.

They are solid steel rather than your alloy version, so your bike will go up in weight a bit.

(even lower-end cranksets might be cheaper still, but the chainrings are not removable)