There’s a selection of historical sketches of such actions in Bryan Perrett’s book, with the obvious title “Last Stands”:
Of these, I have always thought Sidi N’sir the most interesting, 5th Hampshires and 155 Bty RA in Tunisia. Unfortunately 155 Bty seens to have been dsbanded, but the traditions of the Hampshire Regiment are maintained by the PWRR.
A game of Isandlwhana I played many years ago was unusual in that it had rules for ammunition conservation, and, as I wrote in “The Nugget” at the time, nothing concentrates your mind on the question of ammunition conservation more than being speared to death by Zulus.
I think the last stands I would be most interested in re-creating on the table top — all post-1945 — are the BATT at Mirbat, 6 RAR at Long Tan, and the IDF’s 7th armoured brigade in the Valley of Tears. All astonishing defensive battles, and possibly failing the strict test of being “last stands” because, in each case, against all expectation the defenders emerged victorious.
All the best,