do a 1 9/16" (40mm) T-track. Is that going to be of any use? If so, the relevant Harken
part numbers are 1888, B206 & B207.
For the price
Harken / Ronstan et.al. charge per foot for track, it might be worth checking out the price
for 1" x 1.5" or 1.5" x 1.5" rectangular section barstock and get a quote from a machine shop on machining it to your required section?