What might a good to great 20uF film/foil capacitor for a woofer.

I’m building Type B-2 crossover for Klipsch Cornwall’s. I’ve done a couple of pairs so far and they sound great. So much better than the stock B crossovers. I would like to build even better type B-2’s using different caps for the lower frequencies. I’ve come across some B-2 crossovers online for sale yet they use low-grade bobbin Inductor coils. I have been using 2.50mH 16 ga EQ Perfect Lay Hollow Air inductor coils by Erse, great coils, lately I haven’t been able to get them. The longest backorder time ever, several months now. I switched to Jantzen Audio’s Litz Wire Wax coils, offering 0,15 Ω | 3% | 15 awg. I have been using Jantzens Supreme Z 3uf, and 4uf capacitors and will continue using them. I like them better than Mundorfs Supreme S/O oil caps as good as they are. Too spendy for what you get compared to the Jantzen Supreme Z caps. I’ve been using Erse’s 20uf 400v caps. I would like to try something else (20uF caps) for the lower frequency. Any suggestions on good 20-22uF caps that would improve the lower frequencies and not cost a whole bunch? Thank you.