I have a heavy duty TAL mount head (GEM3RA) for sale. It is an older model and does not include a motor drive, though the housing will readily accept the addition of your motor (with appropriate shaft gear). This is a very heavy duty mount with a capacity of ~30 pounds or more. It should be suitable for a medium sized SCT (10" max probably), a larger refractor or 8" newt.
The base has an OD of 75mm (2 15/16"), so it could be used with a 3" or larger pier or with the right tripod. The mount is made from very solid components and nicely machined gears (brass worm gear and massive spring clutch in RA; worm gear control of altitude motion). Movement is controlled by worms on both axes, with manual slo-mo controls on both. A counterweight shaft and counterweight are included (not shown in pic), though you may need to add more weight for larger scopes (this uses standard Vixen/Meade/Celestron/Orion weights). A polar scope is not included.
Price is $160 US including shipping to Canada or ConUS.
P.S. I have lots more pictures of the mount available upon request.