I don't think there could be such a thing as a clone recipe. Mostly because a Helles is not really the product of a recipe, but of a process.
The recipe will invariably be >90% Pilsner malt, maybe a bit of some more characterful malt, then some German hop for bittering and maybe a small flavour addition towards the end of the boil, cold fermentation with lots of healthy yeast.
It's not like you'd just have to find the right hop or character malt to make a clone of Hofbräu rather than Paulaner. Hundreds of breweries in Bavaria brew their Helles with very similar recipes, yet the outcome is often quite different. But that has very little to do with the ingredients used. It's not like they have their secret house recipe which calls for Spalt at 25 minutes which distinguishes it from all the other Helles'.
It's more the result of all the surrounding parameters of the brewhouse, the fermentation method, etc, none of which could actually really be translated to a homebrew setting.
You can brew a Helles and think of the Hofbräuhaus when you drink it, that's the best you can do. For an authentic feel of the atmosphere at Hofbräuhaus and the unfriendly staff, I can record myself ranting in Bavarian, if you like.
Cheers from Munich,
~ Daniel