change old id's(values) with new id's

Hi,

I'm trying to change old id's with new id's in a categories column. (and if possible also change the seperator character used)
This is the data so you can visualize the problem but I also added a excel file so you can see it better or to test with.

(column A in sheet 1)
old id's
53
10
110
30

(column B in sheet 1)
new id's
2
20
120
39

(in column J in sheet 2)
categories
10###53
53
10###30###53
110
110###10
30

The numbers above should become what you see here under. (I also changed the # in a , (comma))
[edit: I should have said that it's always three # that has to change into one comma]
So 10 becomes 20 and 52 becomes 2 and so on.

categories
20,2
2
20,39,2
120
120,2
39

The numbers in categories are the old id's and they have to be replaced by the new id's (from column B) and if possible replace the # character by a , (comma).
Maybe something like vlookup or a find a replace can be used here in a macro?
Also you see that it's possible that in one cell there are 2 or more categories id like 110###10 and this should become 120 and 2 so 120,2
[edit: I should have said that it's always three # that has to change into one comma]

I've added the file in attachment with column A and B in sheet 1, and in sheet 2 you have column J with the categories and sheet 3 has what it has to become.

ps: in column A I just used 4 numbers but there are over a hundred in reality

Thanks so much in advance.

Example_rs_hs_categories.xlsx