Sorry, I'm confused. The Octopod is an elastic or nylon single pass strap with a deployant clasp. (Zuludiver recently added a two-piece alternative as well.) Anchor Straps sells an elastic and a nylon single pass strap with a deployant clasp. That would seem to be a reasonable alternative.
But it sounds from the above comment that you want to re-use Zuludiver elastic straps with a less expensive clasp. If that's the case, my apologies for misinterpreting. There may be a Zuludiver clasp knock-off on Ali Express, but I'm not aware of any clasp that would work with unmodified Zuludiver straps.
There are several options for single pass elastic straps with different clasp approaches.
Erika's Originals is probably the best known, but there is also
Nick Mankey Designs,
The Watch Steward, and
Luff Watchstrap, as well as various inexpensive sellers on Amazon, etc.