I would be inclined to agree with Kevin. Most of the Hansen lures are ideal for sea trout. If I was to pick a favourite, it would be the blue/silver Pilgrim. Some other manufacturers make similar silda type lures which will work too. Also worth looking at the Westin inline lures, such as the D360 and Sommet, although you'd probably have to purchase from Denmark or Sweden
Pink/White is a good colour combo but the classic is of course Blue/Silver. Hansen lures are great also worth looking at LRF metal jigs ... in and around 5 - 7g. Anything small, slim is usually a good bet.
I have also had sea trout on soft lures such as the FBM 70mm and some other small shrimp patterns.
They can be very fussy eaters but really good sport due to the challenge of catching and keeping them on the line ... double split rings is usually a good idea. Also found singles produce a better hook hold.
Here's an interesting article I found today for anyone who's thinking of targeting them , especially the bit about Ragworm Migrations, this is something I had discovered myself while fishing the Straits and Anglesey :-
Call me old fashioned,but...I had two in two casts yesterday evening on a size 3 Mepps Aglia long.You do not need to spend loads on modern lures.....although I suppose I do that anyone! Whatever you use think about depth and speed....good luck!
Hi Gary I will be hitting the water as soon as i can i am hoping to have my licence delivered this week and hope to add a lure caught seatrout caught in the sea to the ones that i have caught on a maggot on a teal and silver in freshwater.