Footwear for sling in winter

[Dazedandconfused101]

Can anyone recommend decent soft sole shoes/ booties for baby wearing in the winter? DS3 isn't ready for 'proper' shoes yet, but looking for something that will keep his feet nice and cosy while we're out and about as I'll be using the sling more regularly than the buggy. He's a big 10 month old, so I find the normal baby booties don't fit/ keep his feet warm enough.

[REW2016]

I realise this is a late reply but have a look at Mocc Ons, and similar ones, they are brilliant for slings and cover chilly ankles.