There is no parish in Sweden today named just "Ryr". Instead, all the "Ryr" parishes have been given compound names by adding something in front of "-Ryr". In fact, there are three(!!) possible Ryr parishes that could be the origin of Lars Magnus Johansson. Valbo-Ryr is in Dalsland province, within the boundaries of the former Älvsborg county. Lane-Ryr is in Bohuslän province, within the borders of the former Göteborg & Bohus county. Väne-Ryr is in Västergötland province, Älvsborg county. The latter two are roughly equidistant from Frändefors (12-15 km) and Valbo-Ryr appears to be just slightly further afield (20-25 km?). Based solely on proximity to Frändefors, I couldn't suggest one over the other. Might have to search records from them all.
Since the website Släktdata (http://www.slaktdata.org/
) has transcribed births for all three parishes, I did a quick search for Lars Magnus' birth but found no obvious matches.