IW379901 folding clasp incl strap

I'm looking for a replacement strap for my IW379901 Top Gun (22 mm lug) to use with a matching fold clasp. Three questions:

1. Is there an IWC part number for a 18/22 Top Gun kevlar strap that can hold a fold clasp, and would the fold clasp + strap from the 48 mm Big Pilot IW501901 fit my IW379901?
2. Does the fold clasp version of the kevlar straps come in three lengths, just like the regular ones do?
3. What is the IWC part number for a matte finish fold clasp that matches the titanium of the 3799? From what I gather these don't come in the titanium look?

Thank you in advance!

Found some answers that may benefit someone else that may be looking for Top Gun replacement straps:

1. The strap used on the modern Big Pilot Top Gun is the IWA51386.
2. Yes, the IWA51386 does come in three lengths: IWA51386 (regular), and IWA51387 XS and IWA51388 XL. Price ca 230 Euro.
3. The IWC part number for the all blasted matching folding clasp (deployant clasp) is IWE03507. Price ca 400 Euro.