I've heard people try parti-gyle with this beer before with varying success. There just isn't much sugars left in the grain after the sparge in this recipe. But let us know how it goes for you if you try
Closest beer to this you might be able to get hold of easily is the ABT12. The brewers of the ABT12 used to brew Westvleteren 12 until the trappist guidelines meant they had to bring it in house. This has lead many to speculate they're born out of the same beer. Some misinterpret it as them being the same beer. They're not. The Westy is drier. That said having tasted the sample from the pre-2014 recipe last night, that's a lot closer to a refined ABT12 that the current recipe. The current recipe really showcases the yeast, syrup, and technique. The pre-2014 is a showcase for EVERYTHING! Waaaay more malt character. I can see why people might have struggled to tell the difference between the pre-2014 recipe and the ABT12 but not the current recipe. Anyway. Bit of a ramble there. This beer really is on its own. I don't know of any other beer on the market that I would specifically say is like it. The slightly odd syrup adjuncts, the strict yeast schedule, and the long ageing process all lead to a very special beer unlike most out there.