Today, 10:54 AM
Is the problem that he won't drink as much cow milk as he is offered, or that he will not stop nursing? The first is probably not a problem at all, and the second is only a problem if you have other desires.
If you child has a reasonably adequate diet of solids and is over 12 months old, I do not see why you have to wean to any type of milk, specifically. Cow milk is not going to replace human breast milk anyway, nutrient wise. In the true sense of the word, when a child weans, they do not wean to bottle of something else, but to a facsimile of an adult diet. By this I mean, children "wean" to sold foods- a (somewhat) varied diet that is as a whole, nutritionally adequate, and may or may not include cow milk products.
Also, must it be in a bottle? Maybe a cup is the answer. Must it be milk? What about yogurt, cheese, etc.
Are you wishing to stop breastfeeding completely right away, or maybe just cut back, stop needing to pump, or other? There are many ways to approach the weaning process.