Miley, 31, joins the club from local rivals City of Liverpool in the summer and has gone on to make 12 appearances for the Purps.
An experienced non-league centre-back, he has previously featured for the likes of Conwy Borough, Colwyn Bay, Bangor City, Bala Town and Marine.
He spent four seasons at the Mariners where he appeared 62 times and scored on six occasions, eventually becoming the club captain.
Joining him at the Berry Street Garage Stadium is Jack Bentley.
The young defender is a part of Tranmere Rovers youth setup and featured for Bootle in their recent 2-2 draw away at Nantwich Town in the Northern Premier League.