Young, 35, made more than 185 appearances for the Bucks but drops down to the EVO-STIK League East Division for a player-coaching role under former boss Martin McIntosh.
The Bucks have now put a seven day approach in for an unnamed centre-back, with a couple of other defensive options also being considered.
Meanwhile, striker Reece Webb-Foster, 20, has arrived from Lancaster City.
He made his debut as a 16-year-old for Bradford City and had loan spells at Bradford Park Avenue, Guiseley and Harrogate Town.
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