Huram, Kent, and Mike,
Not choosing to spend on fancy gear is no indicator of the quality of work you can do with what you do have, and I, for one, won't give you any trouble for not spending big on a meter.
I recommended the Luna Pro F as a long-lived, rugged, versatile meter that you can get a battery for in just about any place imaginable, and a battery that won't go out of production, not because it's expensive or a "status" meter. Since you'd been looking at Luna Pros and had battery concerns, it seemed a natural, and a good used one would be money well spent. I haven't used the Sekonics enough to know them well enough to have an opinion. I also have a Vivitar Model 30 right beside the keyboard here that I'm converting to incident. It requires no battery, and is much lighter and smaller than the Luna Pro F, so it will travel better in a small bag or pocket for fast use with the rangefinders. Use what works for you and what you can afford, and don't bother about what anyone else thinks of what you bought, or what the budget was. You can't buy yourself into being a good photographer, but you can take excellent photos with inexpensive gear.
Have a blast with the Rolleicord. Great camera. I'd like to have one myself.
Lee