<VV> Battery

[Todd Miller]

What is the current recommendation for a battery for a late model?  I have an ACDelco 26RPS in my 69 Monza Convertible.  I believe I purchased it 4-6 years ago.  It has always been on a Battery Tender, but when I went to start it today it was a no crank.  I am guessing that the battery may have just died, as when I hook up my 6 amp charger, I can get a slow turnover.  I can't seem to find a 26RPS online anywhere.  Any other recommended sizes for a Vair?  Thanks.
Todd in TX