1965 & earlier speedometer pinion

Hey fellow mopar people just finished my 4-speed swap in my 65 dart GT. Speedo was perfect before swap, now it reads 8 mph fast! A little resurch found out early 904 has 7 teeth on output shaft. 833/727 have 8 teeth!!!!! (RRRRRRRR!) SO! Inow need a 19 or better yet a 20 tooth early speedo pinion. P.m. me please thanks fellas!