Hi, I talked to Steve just now so here are some pics of both ends.
1620 is stamped on the side and it is 1/2 inch x 17 long.
Your shoes measure 1 inch..the 15-004, mine are shy of that by 1/8 inch..maybe worn I don't know.
Thanks so much,
Kathi
Tom from SWISCO responded:
July 27, 2016
Thank you for posting! Check out our S380-17 side load balance with a spring weight option 1620. Please compare carefully and see if this would be a good fit for you!