Doctors Best D3 is the one that I use so I highly recommend that. Don't forget the important cofactors magnesium and Vit K2-MK7.
Many members use Jarrows B12 sublingual and are happy with them, I prefer Cytoplan.
I see you are intending to purchase from Lucky Vitamin. I know their prices are cheaper than here in the UK, just be aware that there is a limit of £15 for importing purchases from outside the EU, over that amount and you will pay VAT plus a Royal Mail handling fee of £8. The postage is apparently included in the £15. So be very careful to do your sums, you may find it cheaper to buy here.
I don't have time to do price comparisons, but Dolphin Fitness does tend to have the lowest price on most supplements, and if you buy both it qualifies for free P+P. Their service is very good, although the free postage does take about 5 days.
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