if you have too much pressure going into the webber, then you will want to look for a pressure regulator, not another pump.
I'm not sure about your webber, but DCOE's and IDA's like about 2-4psi, and pretty much every unregulated pump in the known universe will outpump that figure, so what ever pump you get you will need a reg on that too. id just throw a reg on a stock pump. its a bit safer using the mechanical pump if you blow a fuel hose anyways!