There is no way to alphabetize a list in Pages. Well, short of doing it manually; cut, paste, cut, paste, etc. . .
However; you can sort a table.
After you have created your table and entered the list, with the table selected, tap the bar above the list so that it turns blue. One of the popup menu items will be Sort.
Using the various table style options (turning on/off grid lines, boarders, etc.) in combination with the arrange options (to place the table where you want it), you should be able to get results similar to a list in appearance.
For bullets, use an extra column with a bullet character and right align it. Or, you can copy and paste individual list items from a list into the table, awkward as that is. While the list feature is not available when entering text into cells, it seems to honor it if you paste already text already formatted as a list.
You won't be able to get exactly the same affect as a list, but this is the only way I can think of to have a sortable list in Pages.