We print them a lot but not direct to the acrylic. Print on display film, then use permanent double sided optically clear mounting adhesive to reverse mount it to the acrylic. Prints reverse mounted this way alway look awesome. Fortunate for us - I have a local shop about 5 miles from here who I can send a vector shape to and they will lasercut the acrylic for me very reasonably. PM me if you want their website or the cheapest supplier I've found for aluminum standoffs. The mounting film we use is General Formulations Concept 106.
Chad,
We print directly on Acrylic. Our only limitation is that our Max print size is 11.75" x 16.5". Here is a link to some of the products we have done. http://recognition-direct.com/awards/acrylic-blocks We sell to re-sellers.
I have done this for other applications, but the client has requested direct print. I guess they had some in the past that over time had shrinkage and showed an adhesive line around the edges.
The client wants "direct print" ...so that's why the op needs a source...How about using cast instead of calendered?