This place has them for sale http://www.tokyofixedgear.com/shopdi...Complete+Bikes - seems they have two small-wheeled mini-velos; the Cycroc and the Bruno Ventura Flat - both very nice but a bit pricey.... A good starting point though? Don't forget a non-seperable Moulton is basically a minivelo too...
OR a non-folding Twenty- like my 24" wheeled beastie.

Bruno Ventura (Very nice retro)

converts to:



Cycroc


Moulton:


Raleigh Shopper
Old

New

Mine



Also google for : Pacific Reach, Cannondale Hooligan, F1 BMX frames...