bannie, have you tried looking on e bay for the issue???If you know the edition, most public library has all of Life magazine on microfilm.
We don't know the issue, but it was in either 1944 or 1945. We also don't know if it was in LIFE or in LOOK. Each one had 52 copies each year. Really, I have just begun my search in earnest. As I said, I have several copies of LIFE headed my way. Each of them mentioned some aspect of Tarawa. :-) Dad's 87, so I'm looking harder than before.