Old money essentially funding upper-class jazzmen (6)

I haven't cracked this one yet — but the brilliant team at Fifteensquared have:

Middle letter (essentially) of [fun] D [ing] + U (slang for upper-class, as in “U and non-U”) + CATS (slang for jazz musicians or those who enjoy listening to them). Coins used for trading in Europe during the 12th – 19th centuries; there are several references to them in Shakespeare plays.