I will conduct a research for these and publish the results here.

Very interesting Nektarios
Strange that the register number for the ex-French one is so elusive.

Three small AGIA PARASKEVI tugs active in the recent years.
If the data provided by Aleksi in the description is correct then this is :

AGIA PARASKEVI, built 1957. 52 gt, call sign SV6143, registered at Piraeus (off. no 2754). Initially owned by Kronos tugs, later by Fenia Naftiki Eteria (Petros Bakas is the owner in both companies).

There were 2 others :

AGIA PARASKEVI, built 1955, Reg. at Piraeus (off. no 2298) owned by Athenian Tugs Shipping Co.

AGIA PARASKEVI, ex. THESEUS, ex. PROVENCAL 5, built 1951, 89 gt, owned by Greek Diving Center Ltd (Konstantinos Nizamis). I have no registry number. This one was sold in 2015.

Any ideas ? Is Aleksi right ?

Only a couple of notes, and not sure where they came from:
AGIA PARASKEVI ex-NISOS POROS ex-BALBUS
reg Piraeus

"Savvas" rings a bell as a local shipbreaker. So perhaps bought at auction 2006?