This sounds like the kind of thing best done by hand, probably with an upholstery needle - but I'm not really sure exactly what you're doing.
Also, remember that rubber stretches - if you punch a hole with a needle, that hole can stretch and tear. Is the area that will be punched reinforced ?
Disclaimer : This post written by a Grumpy Old Man
Actually in the pipes:
- Remaking Ser Loras doublet.
- Luke Skywalker, A New Hope
- Wind Waker starter costume in swim material
Eventually: Paul from Dune, Faramir, Harry Sullivan