Have you considered the SAUM. Norma makes 300SAUM brass now that is cheaper than the WSM Norma brass, and it can be necked down to 7mm. Its a little milder than the 7WSM with less powder but similar velocity and would fit in a short action. I know you said you didn't want a magnum but i think this round has very little bite. Here's a link on alot of the 7's being used in competition. 7mm Cartridge Guide
The 208AI or any one of these calibers would be an awesome choice...decisions decisions!