Yes, but will you really be riding the bike to the point on needing what the ohlins offers? Spending that much for performance shocks, and still having an under performing fork will actually hurt your ride more. Especially if you get really spirited in the twisties or on the track.
Also, looking things up, the thruxton has the same shocks. So, eBay is a definite place to look also. Buying new factory shocks would be expensive and underwhelming, but this are also heavier bikes than the sg400, so the spring rates works probably benefit that bike if you're over the usual 160lbs person they rate most of these bikes for.
Here's a thread some of the triumph guys have any shock upgrades. Maybe they'll lead your to some other options, as well
https://www.triumphrat.net/threads/s...s-mods.972258/