Sure, the RS Pro 2050, the BC 780, 785 or plain 350
The bigger issue is that you will be knocking the signal down by roughly a half to the existing radios (or one of them) when you add this third radio. Best thing to do is determine which of the existing radios has better coverage (probably the CTAF) and split that line in two. The marginal ground stations you are picking up now will probably be gone after another 3dB drop in signal, so you need to organize your radios so that the weakest signals are on the radio at the top of the splitter chain. If the third radio is going to have 133.5, it might need to be on the first splitter in order to pick up the ground side and the most distant aircraft, with the second output on that splitter going to another splitter that feeds the other two radios. Some radios have better ears than others as well (even between two identical models), so you can put them further down the splitter chain. It takes time and experimentation to arrive at the configuration that gets most or all of what you want to hear, most or all of the time, and sometimes that can result in a rather elaborate setup.