Aiming a little high on those recommendations? The OP wants economical and you suggest high end 80s frame material and the Bridgestone RB-1? Your brush paints broad.

The Le Tour can be a great candidate for an SS conversion. Many frames held this name in the 70s and 80s. IMO mid-80s Japanese frames are the sweet spot for value. I've got an $25 1984 Le Tour in my basement waiting for my first SS conversion. It's double-butted 4130. Also had a Japanese made 1986 Puch with a Tange 900 frame that would have been good. Low to mid range Univegas make reasonably light conversions too.

If the OP is concerned about weight, you may want to avoid older frames of 1020 and 2040 steel. I brought back an '83 Motobecane Super Mirage as a commuter this year. It's very pretty, but the frame is 2040 and it's heavy. Rolls ok, but the slightest hill is tough.

And please don't shave off the brazons. That makes a C&V'er cry.