Honours boards have been around a long time and you generally find that local carpentry companies or maybe a DIY guy could make one up pretty easily from a sheet of finished plywood shaped and a wooden beading from B&Q, pinned around it to form whatever type of shape.
However, yours is a bit different from the norm, and I reckon you will rightly be asked to pay a fair whack for what you are getting. Because the arched areas are not “off-the-shelf” mouldings, I suspect they have been routered by hand and pieced in. You then have the wood, staining and varnish process, so even a trade supplier has a bit of work involved in replicating this for you. https://www.goldtreebespoke.co.uk
That said, the cheapest option I can think of manufacturing this is for it to be completely CNC Routered using a decorative cutting bit, from a single sheet of MDF around 20mm thick. (similar to the attached picture of bits) All that would be required is a vector cutting path of the existing board which would be easily traced and replicated from a square on, a photo. What you are then left with is the board as you see it in the picture, but without any woodgrain. As its MDF you will have to primer coat the board and rub it down smooth, then apply the fake woodgrain using a woodgrain tool or brush. You will find lots of different methods to apply a realistic woodgrain effect, similar to the one below, but this is using a woodgrain tool from the likes of B&Q.
Once complete, you have the join of typing up all the names and cutting them in gold vinyl. happy weeding! 🤓😀
regardless of which way you go, trade supplier or DIY, make sure you charge them plenty!
we did two of these a bit like rob has said. a 10x5ft sheet cut to two 5x4ft the extra foot we cut at an angle making it come to a point like a house roof. then a wooden bead around the edges and a decorative edge inside that. stained and varnished and then letter it. the customer loved them.