JJP already has a WOZ based "coin pusher" machine out on location for some years now through his other company Elaut - yes a payout styled machine.
Williams gaming has released a series of WOZ slots (Wicked Witch, Dorothy, Emerald City, a couple of other titles) that are making big money in US casinos (another potential location where the WOZ pins could be sited as redemption style but payout drinks/food discount voucher stubs.)
I really don't get the whole "70 year old granny" thing. The original movie has been played on TV just about every year since I have been on this planet and has been remastered to get another run recently in the BCC/Greater Union nationwide cinema chain.
Everything old is eventually new again.