The real issue here is SWM versus non-SWM. I have a SWM3 LNB at home and a SWM5 LNB I use with the RV. I thought I needed the 119 head to help with alignment of the skew. Now that I have setup the dish a number of times I can tell you, that for temporary use like travelling you can get away with just setting the skew according to the settings suggested on the various dish pointing websites.
And as noted before, there are a number of posts about trouble switching receivers from SWM to non-SWM and vice versa. I can tell you from experience that a receiver set for SWM3 works just fine with a SWM5 LNB without changing any settings.
Your biggest issue is getting things aligned the first time. And if you are going to leave the dish permanently mounted on the dock and just take the receiver back an forth to the boat adding the cost of a meter seems sort of expensive. (Yes, I know you have a boat so maybe $400 to $500 bucks doesn't make that much difference. But, for a one-time setup you can hire someone to come out and do the dish setting and just leave it there.) I justified the cost of a meter (to myself) since I do a lot of setups and teardowns as we travel. Very different than just having a dish on a dock.
So, just match the dish on the dock to what you have at home and you will really minimize any problems with moving the receiver back and forth.