File this away: the Presbyterian Church (USA) has a Sweat-Free Ts program (within its Enough for Everyone), where churches and other entities can order bulk numbers of t-shirts made by an employee-owned venture in Nicaragua. Sure I'd like US made, sweatship free Ts, but this is a pretty-good option and, because there's a clear vendor, is one a church is likely to acutally use. And the cost is competitive with t-shirts sourced from more dubious sources.
Feeling up to another challenge? Enough for Everyone also sources fair-trade coffee, supports church energy audits and investing in Oikocredit. Very cool, and a reasonable venue for interdenominational cooperation.
That link again: Enough for Everyone (PCUSA)