They are obsolete now, and I actually had a pretty hard time finding them when I built the Bayonet earlier this year. I got em from Small Bear too.
Probably could’ve used 5088 or anything really since it’s a Big Muff but I figured, if I can get ‘em why not?
Fortunately it isn’t really a special part. MPSA18 is usually my go to high gain/low noise stuff.