It's a Sprague 673D series. According to the Vishay/Sprague replacement table: https://www.vishay.com/docs/28398/al...placements.pdf The no longer offer a substitution.
MATURED SERIES DESIGN REMARK REPLACEMENT SERIES
673D / U673D Radial General purpose, 105 °C No replacement
Based on the replacement table it appears to be a general purpose aluminum electrolytic capacitor. I would plug in the important values into Digikey's capacitor search and find something comparable. It is 180uF, 105 degrees, 250V. You should also measure the diameter, height, and lead spacing, so you can find one with similar physical characteristic. Being general purpose I suspect +/- 20% on the tolerance.
Digikey had about 50 that meet the basic specs but I do not know the physical size the the sprague.
The UCC were Sprague's low esr series... I think.