The closest I can find on Lovehoney are these blue topped hold-ups but I don’t think the blue will be a close enough match to navy. Lovehoney do quite a few bra/body/babydoll sets in navy but don’t seem to do any hosiery to go with them so maybe you could pop it as a suggestion in the Pander to me! … PRODUCTS ONLY thread. I think the trouble is everyone has a very slightly different definition of navy so all lines are very slightly different shades which makes matching it exactly very hard. I’m afraid we can’t link to any competitor products not sold by Lovehoney on this forum but you can always have a google, they do exist.
To be honest, I would probably just go with black hold ups or you can do black stockings if the set has suspender straps though I do agree it doesnt look quite as good (but is what this model has on)… or as @Sehara says, white goes well with navy, I just avoid it in hosiery as I already have tree trunk thighs and don’t want them looking any bigger 
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Pics of the blue top holdups (prob wrong colour) and model with black stocking just for clarity:
