Balance stats:
Body length 33"
Window weight 40 lbs.
Width on body is at 1/2", would 5/8" be correct assumption.
Picture attached.

Thanks for posting! It sounds like you may have something like our Series 600 spiral balance. With your length, it would be S600-33. However, we don't have any tips that would support your sash weight so this would have to be a custom order.
With that said, I'll go ahead and email you a custom order link that you can use to place an order on our website.