I have a few alros's (trailsman's shadow 180 m400's)but I haven't any of the co2 versions but as a guide trailsmans are 300-400 depending if multi bottle hpa tube or co2
rifles are around the 300 mark for single shot to 400 for multi's and walnut stocks a little bit more yours I'd say is in the 350 range
from what I gather they stopped making them as they couldn't get stocks made for them