Is there a good reference comparing the weights of various handguard or rail options for CAR (or MID) length ARs?

I'm trying to build the lightest AR I can. I'm wondering if there are any railed handguard options that are lighter than the standard (non-railed) handguard.

I'm particularly interested in the Troy TRX. I think I need the 7.2 inch version if I'm going to keep the standard front sight at the CAR mount position.

Does anybody have suggestions or knows the weights of the standard CAR length handguard, the Troy TRX 7.2, or other lightweight railed handguard options?

TIA!