Dave, I'm unable to find the specs on the 20A14 right now, but I suspect it's a 3:1 driver transformer. Antique Electronic Supply has a 3:1 driver transformer, their part number P-T124B, that might do the job for you. Their web page is at www.tubesandmore.com/<http://www.tubesandmore.com/> . Jim, W8KGI