XenServer is a good option as well. Working great here.
Xenserver (not eh community edition) does windows virtualization very well! Also with most XenServer setup's (again not community edition) you can give dedicated ram to the VPS which is something you need to ensure you can get the best throughput for SQL and .net
You also have a very realistic budget for this project.
Any SPLA provider should be able to provide this to you (ensure the host is a SPLA provider for they are the only legal ones that can provide this software to you).