Three characters on the .org in the X-for-Y shape. R4T reads as research for treatment, resources for teachers, or rights for tenants.
Resources for teachers is a substantial category. Teaching materials, lesson planning, and professional development are served by a mix of nonprofits, unions, and public bodies, and the naming convention here would be immediately legible to all of them.
Rights for tenants is another strong fit, with housing advocacy organisations active in every major city and a growing political salience behind the work.
Research for treatment suits a medical research charity, of which there are thousands, all competing for attention with names that tend to be long and similar. Three characters is a real differentiator in a crowded sector.
Fixed supply, established convention, and the extension that matches the buyer exactly.
The name is available. Enquiries welcome.