I have been looking over the website and I am very excited about your idea of a workshop.  I also like the idea of writing a grant and buying some materials, which might even be possible through CCV.  They have some "discretionary funds," about which they never quite tell you what qualifies; you just have to ask and see. 
Concerning the service learning element, I have been thinking about your comments about not pissing off Vermont teachers (which you said more eloquently, but you get my drift) and I think this might work better: Student volunteer in a classroom for X number of hours over the course of the semester and based on the reading, develop a lesson plan for a Reggio Emilia-esqe project that kids can do.  They could do child and teacher interviews in the classroom to find out what children were interested in and build it around that. 
I just called Learning Materials Workshop and talked to the owner, Karen Hewitt.  A 1/2 day workshop for 12 or so students would be $850 - maybe a little less because they are VT students.  She is getting out of the actual manufacturing of the blocks and other toys and what is on her website is all she has.  She would customize the workshop to our needs.  She distributes official RE textbooks and videos and they all come from Italy, thus the higher price, but they would be great.  She recommends One City, Many Children as a good background book, then one of the project books to go with it.  I'm still shopping...
I told her the titles we were looking at and for various reasons, she discouraged using them.  One is too old (which we knew), and the other is an American interpretation of the RE approach, which she feels is watered-down. 
She recommended we contact UVMs RE-like program, run by Dee Smith, which I think is a good suggestion.  Students could visit an actual classroom right in Burlington.  In fact, maybe we could have our workshop happen right in one of these classrooms - wouldn't that be fun?