Or just go for the bigger lakes like Lough Ree, Derg etc. where exploring the lakes takes weeks rather than hours and you can also do the river sections. Shannon Navigation is great for all this - attractions to stop at and visit, pubs and restaurants, places to stay / camp etc.
Not sure how SIB's would fare in the bigger locks but they're manned be WI staff so i'd imagine they could accommodate. There were plenty of SIB's with reasonable sized engines knocking about a couple of weeks back while I was there.
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