I am aware of
four examples of the Constantine VLPP without a helmet from Arles.
This coin is illustrated in Sirmium VIII. Études
de Numismatique Danubienne: Trésors, Lingots, Imitations. Monnaies
de Fouilles
IV au XII Siècle on page 43.
This is the coin referred to on Helvetica's site
which used to belong to 'Arles' and now belongs to Beast. 18mm x 20mm,
2.59g
This is my example, which I purchased on E-bay
in 2005.
This example belongs to Jerome Holderman