Hmmm, holy crap I really didn't comment on this topic?
H3N orange sponge, I would call the orange sponge an unbouncy sponge. Not particularly elastic, pretty slow, maybe easy to use for some, possibly the National version is pretty decent but I don't like it much. There are a few rubbers that come close to imitating this. Mainly from ESN the pored sponge hybrid rubbers. Like Joola Golden Tango PS, in a way Rakza Z, Battle 2 Golden, these are just a few I tried. From these probably the Rakza Z is by far the best.
And there is the H3N blue sponge. That is a completely different beast. The blue sponge to me feels very difficult to compress, has a metallic sound on semi-hard contact, but I like it when it always has a metallic sound. It should sound like
@lodro 's basement when he's educating people how to spank some booty. Sorry for the PG18 rating.
So a few rubbers that qualify as a H3N BS alternative from the ones I tried: Yinhe Big Dipper (budget option), Dingtian Young Shine (still budget at 20USD a pop), Battle 2 blue sponge, Tibhar Hybrid K2 (best option for light weight and no boost), Donic Bluegrip C2, Nittaku Hurricane 3 turbo blue, but you need a BMW inline 6 engine for this at least, it's a heavy MOFO at 63-65g cut to Viscaria. No weak ass inline 3 with any turbo trickery will handle the turbo blue.
Honestly speaking for the average westerner, pale skinned, lazy bumm who wants to feel the closest to Ma Long should just buy Tibhar Hybrid K2. If you are a less lazy bumm you should get the Dingtian Young Shine and boost it with 2 layers of Falco tempo long or Seamoon. And if you are a
failure (by Steven He) just get Yinhe Big Dipper. Honestly the Big Dipper is already pretty decent and they give you factory boost and even factory glue layer not to mention 2 plastic covers. I don't know what those Hebei province folks are smoking when they determine pricing but send some to me too, let me fly with you. Btw I <3 Yinhe blades.
Whaha Zwill, wtf Tibhar K2 is not even available in the western world! Well yes, you can tell Mr Tibor Harangozó's sales team to lick a hedgehog, but indeed it's a bit difficult to get this rubber. Aliexpress or Prott or TTNPP will be your friend, they all have it, prott pricing is pretty good too.
If you are a bit more clever like I assume myself to be you can look at Joola Golden Tango (not the PS just the normal) or recently Gewo has started selling Codexx EF 54 Pro. These all look super similar to K2 and K2 pro and they are both available in EU and possibly US too. There is also Donic Bluegrip V1, but as far as I know it is going out of production.
TL;DR My best recommendation is Codexx EF 54 Pro and Dingtian Young Shine.
PS: blade pairing matters, I would not pair blue sponge type stuff with hard outer ply, aka koto. I think Viscaria and similar blades are a bit troublesome with that type of rubber. Limba outer ply feels better. Don't need to be DHS HL5, other limba outer ply works too, I have been testing my Joola Trinity blade and it is very good.