To replicate 100 of them would run ~ $2500 - $7000 depending on where the moulds are made and the quality of material. If they're made in China with a similar material it'd be closer to the bottom of that scale. If they're made in the US with a more robust material it'd be closer to the top. But, these are just estimates. Without formally submitting an existing surface to the moulding company it's impossible to put an exact number on it. But, expect at least $50/surface.
The other option is to go with something simpler (would lack the graphic elements and just be a plain, featureless pad) that could be die cut or CNCd from sheets of neoprene or silicon with a similar weight and durometer for around $600 per 100. Sure, they wouldn't look as cool but they'd be cheap and give you another 30 years of playability. Plus, they could be done quickly. I'm waiting on samples of different materials and durometers and would be happy to send them out to folks to check out before proceeding. Neoprene would be on the cheaper end of the spectrum but is only available in black. With silicon, skies the limit as far as color goes but, of course, the cost would go up.
Finally, I'm still waiting for a response from the folks at Alternate Mode to see about getting the material they use on their DrumKat pads. I'll let you all know as soon as I hear from them.
Please let me know what you all are thinking and if you have any other ideas.