Aren't those just the weapons/parts from the G1 insecticons, maybe modified to fit? That, or custom job. There was a group doing custom, chrome add-ons that never got lift off.
looks like they took them from the TRU reissue insecticon set and added them to the FP figures to me.
you can mod the chrome bits from G1, then use the standard clip attachment from any generations figure (jazz's speakers, wheeljacks tools, etc). the head needs to be modded to fit. this is one i did, i didnt think the other parts fit well enough. my changes were based on a custom by davidlopan, here on the boards. careful with the chrome, its an ugly yellow underneath if it flakes off. i think you can see just a tad of it where i cut the original antennae to meet up with the hinge on the clip.