Have a look at the Atlas bipod ( http://www.tacfiresystems.co.uk/store/rifle-accessories/bipods/accu-shot-atlas-v8-lw17-bipod/ ). Be warned before you do that it looks very, very expensive when compared with the Harris. However, having just bought one to go with my S510, I think it's well worth it. It's beautifully engineered and - I think - much more elegant and in keeping with the S410 than the Harris. No springs, slim profile, lighter.
It's also much more versatile. It does everything the Harris does - panning +/-15 degrees, cant/tilt the same - for instance, but the legs can be moved
