I mentioned Adams in another thread as a potential target. Trading Nurkic for Adams doesn't make sense for Houston as Adams is the better player and is expiring. Traded Center for Center is rare and usually requires other parts, like the multi-team/multiplayer deal with Ayton, Nurkic, Grayson, and Dame. The Suns can't offer multiple players due to CBA rules and don't have any picks they should add either.
As much as some might not like it the, the best piece for a Center is Grayson and his $15.5 million dollar salary. I'd trade Grayson for Adams if Houston sweetened the pot with a protected pick or a handful of 2nd rounders. Houston doesn't have anyone else whose salary could fit between Adams $12.6m and Allen's $15.5m so picks or a third team would need to be added.
With Royce, Dunn, Morris, Tyus, and even Okogie ans Gillepsie all on the roster though the Suns can afford to trade Grayson. It'd even knock around $7 million off the tax bill, as a bonus. Adams is a backup in Houston so he should be available. The Suns would need to wait a little longer, I believe, because Grayson just resigned here. Either mid December or January would be when Grayson would eligible for trade.