Cleaning basement found some boxes of gun stuff from auctions, sales, etc. Found a new set of Lyman Tru-Lock rings. They look to be new, steel and very nice blue. Come to find out the bases for them are hard to come by. I looked on line and they want average $15 per base. I would like to use these on an older rifle. I can’t find a base chart for these. Do anyone have experience with these?