In that case, if you can stand approx 0.7V drop across RS, you can reduce the long-tailed pair to a single NPN transistor. Put its base-emitter junction across RS (with a resistor in series with the base so you don't blow the junction during transient surges), and use its collector to drive the potential divider driving the base of the PNP Adj pullup transistor. Try RS of 3.3R, 2W initially, and see what it limits at. Fine adjustments can be made by tweaking the potential divider feeding the PNP adj pullup, but coarse adjustments will need a different RS. N.B. as it relies on the NPN's Vbe to set the limit, it will decrease with temperature.
If you can guarantee the load will never draw more than 200mA at -1.5V output, you can eliminate the +1.5V bias rail for the pullup transistor and pull Adj up to ground instead. That has the disadvantage that the output will be at approx -1.4V during current limiting, and if its shorted, only the LM337 internal limiting will be effective, and RS will burn up.