Thanks for the information and the link.

That's definitely ON 507162. And there's a view of her in Louisiana at http://www.shipspotting.com/gallery/photo.php?lid=1404003. Unfortunately, I haven't been able to discover her builder's yard, either. Hundreds of tugs have been built at Houma.

David.....Many thanks for the follow up and link.

I think that is the right one (they didn't get to paint out the registration port of Cutoff LA yet).

53gt 36nt, 47.4 x 18.2 x 7.4ft
built 1967 Houma Shipbuilding Co, Houma LA (Yd ??)

since 1982 (and possibly earlier) Donald J Adams, Lockport LA as RITA A (USCG 507162, reg Cutoff LA)

201x sold to Marine Pacific Petroleum, Panama
(they also own LCU 1647 and barge OBO 757)
https://mpp.com.pa/en/equipment/maritime-equipment-1

Thank you for the updated information.

The RITA A you mention is no longer documented in the US. The USCG PortState Information Exchange lists her currently under the Panama flag.