In the years 1849 and 1850, William B. Greene published Equality and Mutual Banking, describing his Christian Mutualism and setting out the details of the real estate based mutual bank. He was at that time, the minister of the Unitarian church in Brookfield, Massachusetts. In 1850 and 1851, he lead a rural agitation-by-petition, by means of which the General Court of Massachusetts was repeatly asked to legalize this updated form of land bank. We know from copies of the petitions in the 1857 The Radical Deficiency of the Existing Circulating Medium that the petitioners included "the Towns of Brookfield, Warren, Ware, &c." Legislative summaries in the Massachusetts Ploughman and New England Journal of Agriculture now let us add the names of Palmer and West Brookfield to the list (as well as the names of a few more citiens involved in the mutual banking agitation.)
If you want to see the area covered, pull up a Mapquest map centered on the town of Warren, MA. The strip between routes 9 and 19, midway between Springfield and Worcester, is the main area of petitions. In the 1850 petition, the towns in the example extend the zone east to the line formed by interstates 190, 290 and 395: north to Fitchburg and south to Oxford.
With dates for several of the mutual banking petitions, it ought to be possible to delve a bit more deeply into the Massachusetts state records. We know the outcome of the petitions: "Upon all the petitions, the Comittee on Banks and Banking, after hearing the arguments of the petitioners, reported simply, "Leave to withdraw"!" But it might still be very useful to get a better sense of the nature and extent of the movement.