I use a 25mm/4.0 Rodenstock/Omega and a 30mm/2.8 Minolta Rokkor-X CE. Both lenses would give you a monster crop. They both will make a 16x20" from a whole Minox frame (8.5x11mm)
Something like this might suit your project:
Link points to a Rodenstock 25mm/4.0 enlarging lens with M39 mount.