Shimanos can be difficult to match up to universal top kits. My old Shimano pole I have found Milo or Maver fit. However my Daiwa T pro pole fitted the Fireblood top kits.
Its the taper that seems to change.
Most good retailers will let you try out several options so if you want to go down this road take your no4 along and have a play.
As for Shimano exiting pole business I am not so sure although did they ever replace Alan Scothorne and Steve Ringer who both used to endorse their products?
If I am not mistaken Rob Wooten still represents them.