Use it and paint it, before it goes rusty again, at the end of the season.
Painted anchors are quite common. Try to use a bight paint, over a primer, if the water is clear its easier to see on the seabed - and you can then take pretty pictures. We use any old paint left over, but red, fluor yellow/orange, yellow - all work well (for us).
My Delta looked very similar to yours. I painted it with etch primer followed by aluminium paints in aerosol cans from a DIY shop in Corsica. Worked surprisingly well for a long time. Ultimately the answer is to regalvanise but you will come up against the minimum weight hurdle, so you need to find three or four others who,want theirs done.
My Rocna is more rusty that that, I painted it white this year which is great for seeing it underwater in the Med, but ordinary Greek domestic paint has not lasted well and I will do it again next year.
If you use any galvanised anchor, and it sets, the galvanising will wear off and it will rust.
If you want to have an always shiny anchor you need to buy a stainless one. Available in the Delta, Spade and Ultra ranges.
I have regularly sharpened and re-galvanised my CQR but it's now so badly worn that I'm replacing it. The problems with re-galvanising are the one already referred to by Vyv (most galvanisers have a minimum load of 250Kg) and the risk that regalvanising will affect those anchors with hi-tensile shanks (of which the Delta is one). For that reason my new anchor has a detachable fluke, roll-bar and shank.
PS You could always choose to anchor in mud where no wear will take place, but the relatively small fluke area of the Delta will place it at a disadvantage to many other anchors.
My kedge Delta, used for bows-to mooring usually in mud, has not worn the galvanising on the flukes, but it has fallen off the back - basically bad galvanising with very thin coverage @ 90 degrees edges.