You don't outline the details of the project, but if the project is for the client, why would they object to hosting a server if that's what the solution entails?
Here are some questions to consider...
Have you approached the client with the possibility that the solution will entail a dedicated server at their site?
Is this project a long-term thing or a short term project? If it's long term, you may have to work with their IT people because the system may need to be put on their domain, they would need to see if the server is configured to their specs, and be put into the backup system, and there may be issues with allowing you access to their network.
Have you looked at other rendering engines that don't require the graphics card to be installed?
Have you tested with different forms of virtualization that may be usable until a hosting solution instead, like VMWare?
Can you use a colocation service with an ISP or provider in the area?
Asking SF about this isn't going to give a definite answer...we're not the client. No doubt people here have had clients that would say yes and clients that would say no, and it would depend on the policies of the client. Is it okay to ask? Yeah, sure, if that's what the project requires and you've taken reasonable measures to find alternatives that would work for them that wouldn't inconvenience them.
Final answer...go ahead and ask them.