I own a Studio Projects LSD2 and it's a fine mic, but I don't know if I'd use it for nature/soundscape recordings. First of all, it's not super quiet, especially for a LDC. Secondly, it's a BIG mic and I would not want to be lugging it around outdoors.
You might want to consider the Audio Technica BP4025. It's phantom power only, a little quieter than a 825 or a 4022, with higher output.
If you want to take a chance, the MXL V67Q is about $200 street. It appears to be a couple of 603/991/generic Chinese SDC capsules mounted in an XY configuration in a V67 body. On paper it looks good, and perhaps with a mod from Busman or Michael Joly it could be a real sleeper. Like I say, it's a gamble.
Or save your pennies and get something out of the Sennheiser MKH line: very quiet, very high output, very smooth, very expensive.