Yeah I’ve been trying to get a hold of them, but they’re hefty initial price for one use puts me off, and then you usually have to pay another big whack for ‘pyro postage’.
Theres a company coming out with a spring grenade that resembles m26 grenades. I plan on picking a couple up. Thunder B’s with soundflash shells on them are also close enough to MK3A2 concussion grenades. That’s my next purchase.