Hi Dean,
I do have a Colt flight manual. It has excellent takeoff performance charts. To summarize them: At sea level, 40 degree day, 1400 pound takeoff weight, no wind, ground roll 790 feet, 50' 1170 feet, 20 MPH wind g.r. 280', 50' - 540'. At 1650 pounds, 1330', 1820', 500', 900' for the same conditions. If you need more detailed information from that, or any of the Cessna 150 flight manuals, I will figure out how to get it to you.
It does appear that you have cracked open the age old discussion on the performance of C150 vs C152. The factory 152's suffered in takeoff performance and low speed climb because of the choice of propeller. It was a good prop in cruise, but you can't have it all ways. The lackluster takeoff performance was probably the reason for the flap travel being limited to 30 degrees instead of the 40 of the 150. If you do a full flap go around, and circuit (presuming flap system failed at full flap) the performance of the 152 struggles to match that of the 150 at 40 flap.
If the 150 in question is model earlier than 1969, and you have a 50" or 52" prop, you will probably find cruise (and takeoff) performance similar to the original 152. Certainly, the 152 has been the subject of many performance improvement mods. The only one I have experience with is the Sparrowhawk - a very worthwhile mod, particularly with a STOL kit.
A final thought to convey the sense of confidence of C152 short field performance is that my good friend, who is very skilled, and owns several Cessnas, including an original 152 Aerobat, flies it from his 2600' grass runway with great caution, but will not fly it into my 2100' no obstacle grass runway, due to takeoff performance concern. He has flown his C185 amphib, and many other types in here with no problem. I too would be cautious with a 152 in here, though very happliy operated my 150, a 182RG and Twin Otter (among many other types) when it was only 1300 feet long.
I hope that helps. If you need the flight manual data, let me know...
Cheers, Pilot DAR