Haines grand rep springs (again)

[J Patrick Draine]

Dear List:
A few weeks ago someone posted regarding a Haines grand she was working on.
I think I was the only one who responded on the list, and I was for the
most part commiserating with her that their disintegrating springs can be
an awful morrass.
I did, however, ask for suggestions regarding replacing the "repetition
springs" on this action. These Haines actions don't have a repetition
lever, rather the spring itself functions as lever and letoff tip.
Does anyone have recommendations as to the ideal replacement wire? I recall
using various sizes of music wire (brass and steel) to kludge my way out of
situations, but they never seemed satisfactory. I may need to do a whole
set in the near future, and would appreciate informed suggestions. Do any
suppliers sell straight (or spooled) pieces of the same wire used for, say,
Steinway grand wippens?
TIA,
aptrick Draine