I got one in a brow and lash kit from Bare Escentuals when QVC had a “one time only value”. They sell them alone, too. Here’s the info from
http://www.qvc.com/qic/qvcapp.aspx/app.detail.
Item Number A65069. Bare Escentuals Lash Comb. QVC Price $10.00. Shipping and Handling $3.97. Smooth out your lashes with this Bare Escentuals Metal Lash Comb. With metal teeth, it looks and works with professional appeal. Gently comb through lashes starting at the lash line and working outward to eliminate clumps. Clean with a gentle cleanser and dry thoroughly with a soft cloth. Measures approximately 5-1/2"L. Made in USA.
I love mine. The “plastic” lash and brow brushes don’t do it for me.
I don't know if Target or Smashbox have them in their brush line. I know Smashbox used to have the mascara wand/metal lash comb brush, but I didn't see it on their website. You might trying calling their 1-800 no. HTH