Why not go all the way, lets borrow the code from the previous answer and than put in in the Commerce Engine. 

 1. Create a custom index handler
 2. Update the json config - PlugIn.Search.Solr.PolicySet-1.0.0.json
 3. Do a bootstrap, and don't forget to stop start your Minions service. So the the index minions are updated. 

Custom Index handler:

    public class PriceHandler : AbstractIndexFieldHandler
        {
    
    
            public ComposerValueSource ComposerSource { get; set; } = new ComposerValueSource(string.Empty, string.Empty);
    
    
            public override object ComposeValue(object source, ConcurrentDictionary<string, object> context)
            {
                if (context == null || !(source is CatalogItemBase catalogItemBase))
                    return null;
    
    
                if (!(catalogItemBase is SellableItem))
                    return null;
    
    
                SellableItem sellabelItem = catalogItemBase as SellableItem;
    
                if (ComposerSource.PropertyName.Equals("ListPrice"))
                {
                    var pricesPolicy = sellabelItem.GetPolicies<ListPricingPolicy>();
                    var prices = pricesPolicy.SelectMany(pricePolicy => pricePolicy.Prices).Select(money => money.Amount)
                                .ToList();
    
                    return prices.FirstOrDefault();
                }
    
    
                return null;
    
            }
        }

PlugIn.Search.Solr.PolicySet-1.0.0.json:

    {
                "$type": "Sitecore.Commerce.Plugin.Search.Solr.SolrIndexFieldConfiguration, Sitecore.Commerce.Plugin.Search.Solr",
                "Name": "ListPrice",
                "Type": "System.Decimal",
                "Handler": {
                  "$type": "MyCompany.Commerce.Plugin.Pricing.IndexFields.PriceHandler, MyCompany.Commerce.Plugin.Pricing"
                }
              }