I do not want to go to the custom rifle stock route. At least there is not a bolt on these air rifles from what I can see so that really does not require a air rifle to be a lefty. When you say uni stock I presume you mean these rifles are not geared for a RH or LH shooter but rather it fits both RH and LH shooters?

I saw someone mention Sampler from some websites and this helps as there are literally thousands listed to try.