Good online source for MH ballast capacitor?

Hi folks-

In response to some feedback in a thread about my MH lighting system
repeatedly blowing the GFCI protector, I'm now thinking the capacitors
on the transformers are the likely culprit. Long story, but it's my best
theory so far and I'm wanting to change them out.

They are Magnetek VC10040CBTR 005-1184-MF.

You'd think that with that info a quick google search would turn up
plenty of suppliers but I'm having trouble.

I pull up a couple hits showing indeed this capacitor is commonly used
with MH transformer circuitry, but haven't found a place that actually
sells just the capacitors.

Any help in finding an online source (in the US) appreciated.

Sincerely,

Marc