.040 Over
http://www.summitracing.com/parts/UEM-KB243-040/
.060 over
http://www.summitracing.com/parts/UEM-KB243-060/
If you can get by with .030 over, these are the ones I have in my 340
http://www.summitracing.com/parts/ROS-99625/ Flat
http://www.summitracing.com/parts/ROS-99626/ Dome (if you prefer)