Yeah, look for "shell reamer arbor" in a good general tooling catalog and you will find lots of holders. Like shell mill arbors, one shell reamer arbor is designed for a target range of cutter diameters. Unlike shell mill arbors, the shell reamer arbor has a very shallow taper which retains the reamer, where the shell mill arbor has a cylindrical arbor and the mill is retained by a screw in a counterbore in the mill. Measure the ID at each end of those reamers and see if the cutting end isn't slightly smaller than the end notched for the arbor keys.
The taper on shell reamers (in the SAE/inch world) has been standard for quite a while, so you needn't worry too much about getting a shell reamer arbor that fits. Measure the OD of the reamer and get an arbor whose diameter range covers that size.
