It’s really impossible to predict what will be available at this point even going by what’s still in production. Production on any given tape could end tomorrow. However, seeing as how 468 was more or less the defacto go-to tape for Nagra, I would stick with it. You can still find New-Old-Stock PEM468 from AGFA, SM468 from BASF/EMTEC and buy new SM468 from RMGI. In my experience AGFA, BASF and EMTEC 468 are a bit better QC wise, but RMGI is pretty good. No need for rebiasing for any 468… it’s basically the same since its introduction by AGFA, unless you’re into fine tweaking even between different batches. It’s easy enough to do on your Nagra. Personally I look for NOS 468 from the old manufacturers before looking to RMGI. Another thing is they want too damn much for new tape. Under RMGI, SM468 on 7” plastic reel has more than doubled in price in the last few years. That’s too much.