Looking for standard front springs for F800GS 2010 model

I realise this is swimming against the current, but I am now at my wits end with a slight front end vibration at any speed and suspension settings.  It almost feels like an unbalanced front wheel, but I had this checked a couple of times.  The steering head bearing was replaced (ca 45 000 km), as well as a badly worn front tyre, which I suspect was exacerbated by the constant vibration.

I do 90% of my travel on tar, and I do not plan to jump the bike any time soon, so I do not want to spend a large amount on a suspension upgrade.    I bought the bike with Hyperpro springs, and I suspect that it could possibly be the problem.  I am therefore planning to fit the standard springs again, hopefully solving the vibration problem.  I am therefore looking for a set of used standard springs, with relatively low mileage if possible.